The
coastline of Pakistan extends 1,050 km (650 mi), 250 km falling
in Sind province and 800 km in Balochistan. It borders the
productive NE Arabian Sea famous for its upwelling phenomenon.
Its Exclusive Economic Zone (EEZ) covers an area of 196,600
sq.km. and the territorial waters cover an area of 24,000 km2.
The continental shelf of the Sindh coast extends to a distance
of 150 km whereas that of Balochistan only measures 15-40 km.
The prevailing ocean current direction is clockwise during the
southwest monsoon season and anti-clockwise during the northeast
monsoon season. The salinity value is generally 36 ppt. Tides
are neither very high nor very low, but intermediate; the mean
average height is about 10-11 feet. Tides are higher on the
eastern side and their velocity is generally between 1-2 knots
but may increase to 4 knots in narrow creeks.

The
Makran Coast Range forms a narrow strip of mountains along about
75 percent of the total coast length, or about 800 km (500 mi).
These steep mountains rise to an elevation of up to 1,500 m
(5,000 ft). Most of the coast is underdeveloped, with deserted
beaches and only a few fishing villages.

The
coast is rugged and tectonic in origin as evidenced by the
uplifted terraces, headlands and fluted beds. The mud volcanoes
present along the shores further support this. The coastline is
mostly bare desert with unique landforms such as sandy beaches,
mud flats, rocky cliffs, headlands, bays, deltas, etc. Brief
descriptions of these are given in the following section.

Habitat
Types along Pakistan's Coastline:

BeachesSandy beaches are common along Balochistan's shores but rare
in Sindh. Well-known beaches in Pakistan include Somniani,
Hingol River, Ormara, Pasni, and Gawadar in Balochistan, and
Clifton and Hawks Bay in Sindh.

Cliffs
and HeadlandsRocky shores and cliffs are prevalent in Balochistan. They
are generally composed of conglomerates of soft mudstone and
sandstone, which are highly susceptible to erosion. Headlands
are prominent in Jiwani, Pisukan, Gawadar Rasjaddi and Ormara,
and are intervened by low-lying places comprised of alluvial
deposits. Irregular cliffs present at Ras Malan are a result of
tectonic activity. Several deep-seated faults are also evident.
The Sindh coast on the other hand, is very poor in rocky shores.
Buleji, Manora Rocky Ledge, Cape Monze, and a few other small
sites are present in the extreme western part of the province.
The steep cliffs at Cape Monze are a trajectory of Mor and
Kirthar Ranges, and are composed of hard limestone.

Bays
and lagoons
Bays and lagoons are protected bodies of water surrounded by
land having an opening into the sea. In bays, the opening is
wide, whereas in lagoons it is very narrow. There are no bays or
lagoons along the Sindh coast, but several along the Balochistan
coast, such as Gawadar Bay, Ormara Bay and Somniani Bay. Sandy
coasts in a curvilinear pattern fringe the first three mentioned
bays, which are slowly being destroyed by erosion. There are
only two lagoons in the country, both of which are also located
in Balochistan. These are the lagoons of Kalmat Khor and Miani
Hor, which harbor dense mangrove vegetation on the insides.

Mud
FlatsMud flats are gently sloping, unconsolidated inter-tidal
parts of estuaries, and are always occupied by marsh vegetation.
Tidal flats are the same except that they lack vegetation. The
entire Indus Delta and most of the Sindh coast is comprised of
mud flats with mangrove vegetation. Mud flats are nonexistent in
Balochistan except in Gawadar Bay, Kalmat Khor and Miani Hor
lagoons.

Mud
Volcanoes
Mud volcanoes are conical hills or mountains with a crater on
top through which they gently emit liquid, mud and gas. They are
commonly associated with petroleum deposits, hence their
presence indicates high petroleum potential along the Makran
coast. Mud volcanoes generally emit muddy and saline water, but
occasionally large masses of rock are violently blown hundreds
of feet into the air. The gases that are discharged include
methane, ethane and traces of unsaturated hydrocarbons. Mud
volcanoes are a common occurrence in Balochistan but are not
found in Sindh.

Estuaries
Estuaries are coastal embankments that receive substantial
freshwater runoff from land, and experience open tidal
circulation with the ocean. In other words, estuaries are the
mouths of rivers opening into the sea. There are three major
estuaries in Pakistan, the largest one being the Indus estuary
on the Sindh coast. The other two are the Hingol and Dasht
estuaries both located in Balochistan.

Deltas
Deltas are an accumulation of sediments at the mouths of rivers
where they empty into basins. Deltas consist of three major
parts: the delta plain, delta front and prodelta. There are
several small deltas at the mouths of seasonal rivers in
Balochistan. However, one of the largest deltas in the world,
the Indus Delta, is located at the mouth of the Indus River and
covers almost the entire coast of Sindh. It forms a remarkably
uniform landform with large extensive mud flats being intervened
by narrow creeks, which are remnants of old, Indus tributaries.
The western part of the delta between Phitti Creek and Karachi
Harbor is now abandoned, although at one time the Indus River
used to flow close to Karachi.